The arthroscopic video camera system of the present invention is of the same general type described in U.S. Pat. No. 4,590,923 which issued May 27, 1986 to the present inventor.
As described in the patent, arthroscopy is a particular form of endoscopy which, in turn, is the art of examining the interior of a body cavity or hollow organ by the use of a thin tubular instrument known as an endoscope. Enscopes have been in common use since the early 20th Century. These instruments include a rigid tube containing lenses and optical glass fibers, and a lighting system by which light from an external source is conducted through the optical glass fibers to the region being examined. Endoscopes also commonly contain an irrigation system for introducing fluids, typically normal saline solutions, to the region being examined. The development of arthroscopy and instruments adapted for arthroscopic examinations, known specifically as arthroscopes, are described in an article entitled "Arthroscopy of the Knee" by Robert W. Jackson et al., Modern Orthopedic Monographs, 1976, published by Grune & Stratton, Inc. of New York.
The arthroscope, like the endoscope, is a long tube with a fiber optic light carrier which permit light to be transmitted down the tube into the body, and which further permits the doctor to view the area of the body adjacent to the distal end of the arthroscope. Arthroscopes can be particularly useful in observing the conditions within the human body. One area of the human body which arthroscopic viewing can be extremely useful is in the knee. A surgeon frequently finds it highly desirable to view the postermedial compartment of the knee in order to observe conditions in the compartment and to view the cartilage adjacent to the compartment.
The arthroscope works on the same principle as a telescope, and contains a tube with a fiber optic light carrier that lights up the joint, and glass lenses to reflect the image back to the surgeon. Some arthroscopes provide direct viewing, and others allow for 30.degree.-70.degree. angles.
Video systems for arthroscopy have recently been developed in which the eyepiece of the arthroscope is optically coupled to a video camera, and the arthroscopic images are displayed on the screen of a cathode-ray monitor. Such systems are marketed, for example, by the Stryker Corporation of Kalamazoo, Mich. The present invention, like the system of U.S. Pat. No. 4,590,923, is concerned with arthroscopic video systems, and the principal objective of the invention is to provide an improved arthroscopic video system and assembly.
In order to keep the video camera sterile in the arthroscopic video systems of the prior art, it was the usual practice to cover the video camera with a bag, or to soak the camera in a CIDEX solution. However, soaking the camera is not only time consuming, but does not provide a sterile unit. Soaking also served to decrease the life of the video camera.
In the system described in U.S. Pat. No. 4,590,923 referred to above, in order to overcome the problems of the prior art, the video camera is encased in a housing composed of stainless steel, the housing being first sterilized in an autoclave. In this way, the need for a plastic bag over the camera, or the need to soak the camera in a CIDEX solution, is obviated.
One feature of the system of the present invention is the provision of a sterile disposable plastic housing for the camera, in place of the stainless steel housing described in the patent. The plastic housing is received in a sterilized condition in a convenient package, and is disposed of at the end of the surgical procedure. Accordingly, any need for autoclaving of the housing is eliminated. This is because a new housing is used for each subsequent surgical procedure, with the housing being disposed of at the end of each such surgical procedure.
Accordingly, in the practice of the present invention, the arthroscopic camera has a plastic polymer case which fits directly over the camera. The case is a sterile disposable unit which eliminates the need for the camera bag or for soaking of the camera. The case is inexpensive and in conjunction with the arthroscopic adapter, it seals the camera and keeps it completely sterile.
The disposable sterile case allows for the interchange of the various arthroscopes. In other words, the surgeon is able to switch back and forth from the 30.degree. angle to the 70.degree. angle arthroscope with no difficulty. At the present time it is necessary to remove the plastic cover of the arthroscope by untying a string and retying when a new scope is inserted. Not only is this a very cumbersome method, but there is a significant danger of contamination due to the fact that the eyepiece of the scope is no longer sterile when it is inserted into the camera.
Another problem is that water can leak in from beneath the string area and ruin the camera. The disposable camera case costs about the same as the plastic bag that is presently in use.
Another method commonly used is to soak the camera in a Cidex solution as mentioned above. This serves to clean the camera but not provide complete sterility. This method is not permitted in most hospitals in this area because of the danger of infection. Another problem with the soaking method is that no matter how will sealed the camera, there will eventually be a leak and the solution will ruin the camera. This has been the experience of many hospitals. The soaking may also ruin the arthroscopic adapter and cause the sticking and fogging of the lens system in the adapter.
The disposable camera case of the invention is attractive and allows for ease in handling the camera. At the present time the plastic bag that is in common use causes the camera to slip around and to be difficult to handle. As mentioned, the camera case is provided in a sterile package. The entire system saves valuable operating room time and provides for a much more efficient surgical procedure.